This invention relates to a sewing machine cabinet of the drop head type and more particularly to a mechanism for preventing the unlocking of the machine support platform when in the operative position.
In sewing machine cabinets of the drop head type, the sewing machine support platform is usually manually lifted into the operating position and lowered to its stored position within the cabinet. Means is provided for releasably securing the platform in the operating position. The prior art discloses various arrangements for accomplishing this result. One such arrangement utilizes a catch plate rigidly attached to the sewing machine cabinet and an interacting latch pivotally attached to the machine support platform. The latch is biased into wedging engagement with the catch plate when the machine is in operating position. When storing the machine, it is first pivoted upwardly so that the latch rides up and over the top of the catch plate and out of wedging engagement. The machine and support platform may then be lowered into the stored position. This type of construction is disclosed in U.S. Pat. No. 3,823,993, July 16, 1974, Kakishima et al, the teachings of which are incorporated herein by reference. Another such arrangement, but of somewhat different construction, is disclosed in U.S. Pat. No. 3,830,554, Aug. 20, 1974, Moussaian et al, the teachings of which are incorporated herein by reference. Moussaian discloses a sewing machine cabinet of the drop head type having a pair of bolts mounted on opposite sides of the platform which are received within sockets formed on corresponding keepers pivotally mounted on the cabinet side walls. To place the machine and platform into storage, the platform is pivoted upwardly until the bolts engage an upper surface of the keepers causing them to pivot thereby disengaging the bolts from the sockets. The machine and platform may then be lowered into the stored position. Both of these arrangements utilize one or more hinged flaps which abut the machine when in the operative position. Prior to placing the sewing machine in the stored position, these hinged flaps must be pivoted out of the way to provide sufficient clearance for the machine. A serious difficulty with this construction is evident when one unlatches the mechanism by pivoting the machine upwardly without moving the hinged flaps out of the way. The machine can then be released causing damage to both the machine and the flaps.
The present invention overcomes this disadvantage through the use of a novel but simple mechanism.